Hypoplasia

Distribution by Scientific Domains
Distribution within Medical Sciences

Kinds of Hypoplasia

  • cerebellar hypoplasia
  • enamel hypoplasia
  • focal dermal hypoplasia
  • linear enamel hypoplasia
  • lung hypoplasia
  • nerve hypoplasia
  • optic nerve hypoplasia
  • pulmonary hypoplasia


  • Selected Abstracts


    Acneiform lesions in Becker's nevus and breast hypoplasia

    INTERNATIONAL JOURNAL OF DERMATOLOGY, Issue 10 2002
    Jorge Santos-Juanes PhD
    An 18-year-old woman was referred for the evaluation of a dull gray macule on the left breast. From the age of 13 years, the patient noted breast asymmetry beginning with the development of the left breast and the presence of a pigmented stain on its border. Physical exploration revealed hypoplasia of the left breast and a homogeneous, light brown macule on the side of the breast (Fig. 1) without infiltration. Papules and pustules were located mainly around the Becker's nevus on the left anterior chest wall. Biopsy specimens with Fontana's stain disclosed a hyperpigmented acanthotic epidermis. A diagnosis of Becker's nevus, acne, and hypoplasia of the breast was made. Figure 1. Hypoplasia of the left breast and a homogeneous light brown macule with acneiform lesions [source]


    R2 The pattern of extraction of first permanent molars: results from three dental hospitals

    INTERNATIONAL JOURNAL OF PAEDIATRIC DENTISTRY, Issue 2006
    S. S. ALBADRI
    Objective:, To determine and compare the reasons and pattern of extraction of first permanent molars (FPM) in 3 UK dental hospitals. Design:, Data were collected prospectively from 300 children attending Manchester Dental Hospital (MDH), Liverpool Dental Hospital (LDH) and Charles Clifford Dental Hospital, Sheffield (CCDH) who required extractions of at least one FPM. Information recorded included age, FPM extracted, reason for extractions, previous treatment, method of extraction, and whether patients had previous extractions. Result:, The mean age in months was 129 (Std 22.7), 139 (Std 29.4), and 133 (Std 26.8) for MDH, LDH, CCDH respectively. 45% and 48% of children had four FPM extracted at MDH & CCDH, respectively, compared to 25% in LDH. The main reason for extraction (70%) was caries with poor prognosis, followed by caries and compensating extraction (14%). Molar Incisal Hypoplasia was the reason for extraction in 11% of cases. General anaesthesia was the main anaesthetic method used with 77%, 55%, and 47% in MDH, LDH and CCDH, respectively. Local anaesthesia was used in 43% of cases in LDH in comparison to 12% and 22% in MDH and CCDH, respectively. 68% of children had received no previous treatment to the FPM and only 5% had fissure sealants placed. 40% of children had previous extractions. Conclusion:, The children who are attending our hospitals for extractions of FPM tend to be older than the recommended age for achieving maximum space closure. This study highlights the need for extensive prevention programs targeted at those children with high caries risk. [source]


    Bilateral Systematized Porokeratotic Eccrine Ostial and Dermal Duct Nevus with Unilateral Breast Hypoplasia

    JOURNAL OF CUTANEOUS PATHOLOGY, Issue 1 2005
    A. Jayaraman
    Porokeratotic eccrine ostial and dermal duct nevus (PEODDN) is a rare hamartomatous malformation of the eccrine duct which typically presents at birth or early in life. Multiple punctate pits and verrucous papules and plaques with nonfollicular hyperkeratotic spines are seen over the palms and soles and may extend to the distal extremities. A linear distribution may be present. A wide range of involvement has been reported in the literature, including bilateral systematized involvement. No systemic involvement has been linked to PEODDN to date. Histologic findings are characteristic and include a dilated eccrine acrosyringium with an overlying parakeratotic column or cornoid lamella. There is slight dyskeratosis and loss of the granular layer under the cornoid lamella. Here, we present a case of bilateral systematized PEODDN in an otherwise healthy, 18 year-old Hispanic female. Physical examination is notable for marked hypoplasia of the left breast with overlying verrucous papules and plaques. Multiple punch biopsies were performed and showed findings diagnostic of PEODDN. To our knowledge, this is the most extensive involvement of PEODDN reported in the literature to date and the only case with associated hypoplasia of the breast. [source]


    Esthetic Rehabilitation of Anterior Teeth Affected by Enamel Hypoplasia: A Case Report

    JOURNAL OF ESTHETIC AND RESTORATIVE DENTISTRY, Issue 6 2002
    CARLOS JOSÉ SOARES DDS
    ABSTRACT Alterations during tooth structure formation, mainly on anterior teeth, are known to severely compromise esthetics. This article presents a case report in which the etiology and clinical characteristics of anterior teeth affected by enamel hypoplasia are analyzed. The restoration treatment sequence is also discussed, demonstrating that the use of a hybrid and a microfilled composite associated with tooth hybridization (interdiffusing zone) can be used to conservatively rehabilitate a smile. [source]


    Hypoplasia of the arcuate nucleus and maternal smoking during pregnancy in sudden unexplained perinatal and infant death

    NEUROPATHOLOGY, Issue 4 2004
    Anna Maria Lavezzi
    Maternal smoking during pregnancy is the most important risk factor for sudden perinatal and infant death in more industrialized countries. The frequent observation of hypoplasia of the arcuate nucleus in the brainstem of these victims prompted the verification of whether maternal cigarette smoking could be related to defective development of this nucleus during intrauterine life, by affecting the expression of specific genes involved in its developmental process. In serial sections of the brainstem of 54 cases of sudden and unexplained fetal and infant deaths (13 stillbirths, 7 neonatal deaths and 34 sudden infant death syndrome (SIDS) victims), morphological and morphometrical analysis was used to observe the different structural alterations of the arcuate nucleus (bilateral hypoplasia, monolateral hypoplasia, partial hypoplasia, delayed neuronal maturation and decreased neuronal density) detected in 24 cases (44%). Correlating this finding with smoking in pregnancy, a significantly increased incidence of cytoarchitectural alterations of the arcuate nucleus was found in stillborns and SIDS victims with smoker mothers compared to victims with non-smoker mothers. Moreover, the observation of a wide range of developing morphological defects of the arcuate nucleus related to maternal smoking led to the hypothesis that the constituents of the gas phase in cigarette smoke could directly affect the expression of genes involved in the development of this nucleus, such as the homeobox En-2 gene. [source]


    Giant Congenital Melanocytic Nevus with Underlying Hypoplasia of the Subcutaneous Fat

    PEDIATRIC DERMATOLOGY, Issue 5 2000
    Stephanie A. Caradona M.D.
    The skin overlying the GCMN was persistently warm when compared with the surrounding and contralateral skin. Comparative plain radiography, ultrasonography, and magnetic resonance imaging showed fat hypoplasia of the left lower extremity, with bone and muscle appearing unaffected. The possible role of cytokines produced by the nevus in fat hypoplasia in GCMN is discussed. [source]


    Atypical Fetal Prostate Development is Associated with Ipsilateral Hypoplasia of the Wolffian Ducts in the ACI Rat

    THE ANATOMICAL RECORD : ADVANCES IN INTEGRATIVE ANATOMY AND EVOLUTIONARY BIOLOGY, Issue 5 2010
    Luke E. Hofkamp
    Abstract For over a half century, the ACI (August × Copenhagen) rat has been a primary model for studying renal agenesis and ipsilateral hypoplasia (IHP) of the Wolffian-derived structures (WDS). Because the ACI rat is also used as a model for prostate research, it is important to examine the relationship of IHP and urogenital sinus (UGS) development. The prostate is dependent on androgens for proper growth and differentiation. Alteration in androgen production and/or delivery to the UGS has the potential to perturbate normal development. In this study, we investigate whether the ipsilateral loss of the WDS is associated with altered prostate development. Digital images of serial-sectioned fetal ACI rat UGS were used to create three-dimensional (3-D) surface-rendered models of the developing prostate, seminal vesicle, vas deferens, and utricle on gestational day 21. The number and volume of prostate ducts developing from the UGS were calculated from the 3-D model data. Animals exhibiting IHP had a significant decrease in total fetal prostate volume (40%; P < 0.005) with significant regional specific differences when compared with normal male ACI rats. Anatomical and histological differences in the utricle, abnormal histology of the ipsilateral testes, and a truncation of the ipsilateral Wolffian ductal mesenchyme were also seen in the animals with IHP. Additional research is needed to further understand the mechanisms and consequences of IHP on prostate growth and development. Alterations to normal prenatal development of the male accessory sex organs can have important consequences for the growth and morphology of the adult gland. Anat Rec, 2010. © 2010 Wiley-Liss, Inc. [source]


    Atypical Fetal Prostate Development is Associated with Ipsilateral Hypoplasia of the Wolffian Ducts in the ACI Rat

    THE ANATOMICAL RECORD : ADVANCES IN INTEGRATIVE ANATOMY AND EVOLUTIONARY BIOLOGY, Issue 5 2010
    Luke E. Hofkamp
    Serial section reconstruction images of the male ACI rat urogenital sinus shown from a dorso-cranial view. The image in the lower right illustrates the normal late gestation appearance of the accessory gland development, compared to the Wolffian duct ipsilateral abnormality observed in 25% of the male offspring (upper left). See Potok et al., Anatomical Record 239:747,753. [source]


    A boy born with multiple lesions of atrophoderma

    ACTA PAEDIATRICA, Issue 3 2010
    Piero Pavone
    Abstract Aims:, The Atrophodermas include a large group of disorders appearing as localized or widespread depressed skin areas and characterized by underlying dermal atrophy. The present study aims to report a peculiar form of previously unreported focal dermal atrophy. Methods:, We studied over a period of 5 years a boy who manifested, since birth, multiple hypopigmented cutaneous atrophic lesions of the atrophoderma type in a mosaic distribution over the body and the legs. Results:, This boy did no develop other cutaneous or systemic stigmata except for an idiopathic thrombocytopenic purpura (ITP) manifested at age 2 years. Full serum, metabolic and infective analyses; full ophthalmological examination; ultrasound examination of the heart and internal organs; skeletal x-rays; brain magnetic resonance imaging; and DNA analysis of the PORCN (Focal Dermal Hypoplasia - FDH) gene in this boy yielded normal results. Pathological analysis of multiple skin specimens from an affected area revealed slightly reduced dermal thickness; hyperpigmentation of the basal layer; homogenized and disarrayed collagen bundles; perivascular chronic infiltrates of lymphocytes and histiocytes; and normal skin appendages. Currently, the child is healthy; he has mildly improved skin status with less-evident skin depression throughout the lesion areas and no further complication has been recorded. The histological and clinical appearance of the skin lesions and the course were against any known disorder in the group of the atrophodermas. Conclusions:, The cutaneous lesions seen in this boy represent a possibly new congenital skin disorder characterized by multiple, benign areas of focal dermal atrophy in a mosaic distribution. [source]


    Developmental toxicity of indium: Embryotoxicity and teratogenicity in experimental animals

    CONGENITAL ANOMALIES, Issue 4 2008
    Mikio Nakajima
    ABSTRACT Indium, a precious metal classified in group 13 (IIIB) in the periodic table, has been used increasingly in the semiconductor industry. Because indium is a rare metal, technology for indium recycling from transparent conducting films for liquid crystal displays is desired, and its safety evaluation is becoming increasingly necessary. The developmental toxicity of indium in experimental animals was summarized. The intravenous or oral administration of indium to pregnant animals causes growth inhibition and the death of embryos in hamsters, rats, and mice. The intravenous administration of indium to pregnant animals causes embryonic or fetal malformation, mainly involving digit and tail deformities, in hamsters and rats. The oral administration of indium also induces fetal malformation in rats and rabbits, but requires higher doses. No teratogenicity has been observed in mice. Caudal hypoplasia, probably due to excessive cell loss by increased apoptosis in the tailbud, in the early postimplantation stage was considered to account for indium-induced tail malformation as a possible pathogenetic mechanism. Findings from in vitro experiments indicated that the embryotoxicity of indium could have direct effects on the conceptuses. Toxicokinetic studies showed that the embryonic exposure concentration was more critical than the exposure time regarding the embryotoxicity of indium. It is considered from these findings that the risk of the developmental toxicity of indium in humans is low, unless an accidentally high level of exposure or unknown toxic interaction occurs because of possible human exposure routes and levels (i.e. oral, very low-level exposure). [source]


    Hyperthermia in utero due to maternal influenza is an environmental risk factor for schizophrenia

    CONGENITAL ANOMALIES, Issue 3 2007
    Marshall J. Edwards
    ABSTRACT A hypothesis is presented that the association between maternal influenza and other causes of fever during the second trimester of pregnancy and the subsequent development of schizophrenia in the child is due to the damage caused by hyperthermia to the developing amygdalohippocampal complex and associated structures in the fetal brain. Hyperthermia is a known cause of congenital defects of the central nervous system and other organs after sufficiently severe exposures during early organogenesis. The pathogenic mechanisms include death of actively dividing neuroblasts, disruption of cell migration and arborization and vascular damage. In experimental studies, hyperthermia during later stages of central nervous system development also caused damage to the developing brainstem that was associated with functional defects. This damage usually results in hypoplasia of the parts undergoing active development at the time of exposure. Recent studies have shown no evidence of direct invasion of the fetus by the influenza virus. Factors that might interact with hyperthermia include familial liability to schizophrenia, season of birth, maternal nutrition, severe stress and medications used to alleviate the symptoms of fevers. The time of the development of the fetal amygdalohippocampal complex and the changes found in its structure and associated areas of the brain are compatible with the known effects of hyperthermia. [source]


    Teratogenic effect of bis-diamine on embryonic rat heart

    CONGENITAL ANOMALIES, Issue 3 2000
    Masao Nakagawa
    ABSTRACT, Bis-diamine induces conotruncal anomalies including persistent truncus arteriosus, tetralogy of Fallot, interruption of the aortic arch, and ventricular septal defect in rat embryos when administered to the mother. Bis-diamine also induces extracardiac malformations including thymic hypoplasia, facial dysmorphism, forelimb anomalies and diaphragmatic hernia. However, the teratogenic mechanisms of this chemical in early developing rat hearts have not been fully established. Chimeric studies in chick and quail embryos demonstrated that the cranial neural crest cells reached the cardiac outflow tract, contributing to aorticopulmonary and truncal septation. Since an ablation of the cranial neural crest also produced the conotruncal anomalies, bis-diamine is proposed to disturb the normal migration of cardiac neural crest cells to the heart. Based on our data concerning cardiac anomalies induced by bis-diamine, we reviewed how the cardiac malformations were morphologically established in early developing rat hearts. Our data showed that 1) cardiovascular anomalies induced by bis-diamine are time- and species or strain- dependent. 2) bis-diamine reduces the number of neural crest cells migrating to participate in the conotruncal septation, 3) bis-diamine induces anomalous coronary arteries, thin ventricular walls and epicardial defects, and 4) some embryos cultured in the medium containing bis-diamine had extra-cardiac abnormalities including abnormal location of the otic placodes and delay in mid brain closure. Conclusively, bis-diamine does not appear to merely affect the cardiac development, but rather disturbs normal development of all the organs contributed to by neural crest cells. [source]


    Early and Midterm Results of an Alternative Procedure to Homografts in Primary Repair of Truncus Arteriosus Communis

    CONGENITAL HEART DISEASE, Issue 3 2010
    Pedro Curi-Curi MD
    ABSTRACT Background., Repair of truncus arteriosus communis (TAC) in the neonatal and early infant period has become a standard practice. We report our experience on primary repair of TAC with a bovine pericardial-valved woven Dacron conduit as an alternative procedure to homografts, with a focus on early and midterm results. Methods., From January 2001 to December 2007, 15 patients with mean age 1.5 years (range 3 months to 8 years), underwent primary repair of simple TAC. Cases with cardiogenic shock, complex-associated cardiac lesions, or adverse anatomy of the truncal valve were excluded. The Collett and Edwards anatomical type classification of TAC was as follows: type I, 13 (87%); and type II, 2 (13%). Right ventricular outflow tract was reconstructed in all the cases with a bovine pericardial-valved woven Dacron conduit. Results., Overall mortality was 6.6% (1 death due to severe pulmonary hypertension). At a mean follow-up of 31 months (range 6,51), there were no deaths (5-year actuarial survival 93.4%). Out of the 14 midterm survivors, three developed stenosis of the pericardial-valved woven Dacron conduit, but only one underwent interventional procedure including percutaneous balloon dilation with stenting for associated left pulmonary artery hypoplasia. The rate of patients with no surgical or percutaneous reinterventions performed because of obstruction of the right ventricular outflow tract reconstruction in the midterm (5 years) was 86%. Conclusions., Truncus arteriosus communis repair with a bovine pericardial-valved woven Dacron conduit can be performed with a very low perioperative mortality and satisfactory midterm morbidity, favorably compared with that reported for the use of homografts. Interventional cardiac catheterization may delay the time of reoperation for inevitable conduit replacement due to stenosis. [source]


    Persistence of Left Supracardinal Vein in an Adult Patient with Heart,Hand Syndrome and Cardiac Pacemaker

    CONGENITAL HEART DISEASE, Issue 3 2008
    Jan Nemec MD
    ABSTRACT A patient with a sporadic heart,hand syndrome, which includes thumb hypoplasia, septum primum atrial septal defect, and cleft mitral valve is described. During attempted placement of a pacemaker lead, persistence of left superior and inferior vena cava was found in addition to the right-sided caval veins. This corresponds to persistence of left-sided supracardinal vein present during fetal development. [source]


    Frequency of intrusive luxation in deciduous teeth and its effects

    DENTAL TRAUMATOLOGY, Issue 4 2010
    Vivian Carvalho
    Second, to investigate the sequelae of total and partial intrusive luxation in the primary anterior teeth and in their successors and finally, to establish whether the sequelae on both deciduous and permanent teeth were related to the child's age at the time of the intrusion. Data collected from records of 169 boys and 138 girls, all between the ages of zero and 10 years, who were undergoing treatment during the period of March 1996 to December 2004. The sample was composed of 753 traumatized deciduous teeth, of which 221 presented intrusive luxation injury. Children with ages ranging from one to 4 years were the most affected with falls being the main cause of intrusion. Of all intruded teeth 128 (57.9%) were totally intruded and 93 (42.1%) partially. Pulp necrosis/premature loss and color change were the most frequent sequelae in both total and partial intrusions. Concerning permanent dentition, the most common disturbances were color change and/or enamel hypoplasia. Both types of intrusion caused eruption disturbance. Total intrusion was the most frequent type of intrusive luxation. There was no significant correlation between the child's age at the time of intrusion and the frequency of subsequent sequela on primary injured teeth (P = 0.035), between the age at the time of injury and the developmental disturbances on permanent teeth (P = 0.140). [source]


    Traumatic injuries to the primary dentition and effects on the permanent successors , a clinical follow-up study

    DENTAL TRAUMATOLOGY, Issue 5 2006
    Sabine Sennhenn-Kirchner
    Abstract,,, This study investigated problems in the permanent dentition that, according to history and records, were attributable to dental alveolar injuries of the primary dentition. 106 children have been involved in the study, who had experienced primary anterior tooth trauma affecting a total of 200 teeth. Thirty-nine patients (81 teeth) were available for follow-up examinations. In 25% of the cases followed up, damage was found on the successors in the secondary dentition (16 children/20 teeth). In half of the cases, a comparatively mild form of lesion like enamel discoloration was observed. This was the result of an injury during the tooth maturation process causing enamel hypoplasia. Clinically more relevant were the dental deformities: cessation of root formation or retention caused by ankylosis, which made up the remaining 50% of cases. This was confirmed by clinical long-term observation. The different effects on the permanent teeth can only be detected by radiography after an interval of several months or may even be clinically assessed only after the eruption of the clinical crown. [source]


    Long-term effect of different treatment modalities for traumatized primary incisors presenting dark coronal discoloration with no other signs of injury

    DENTAL TRAUMATOLOGY, Issue 1 2006
    Gideon Holan
    Abstract,,, The aim was to compare the long-term outcomes of root canal treatment with that of follow-up-only in traumatized primary incisors in which dark discoloration is the only sign of injury. Root canal treatment was performed in 48 dark discolored asymptomatic primary incisors following trauma. Twenty-five of them [root canal treatment (RCT) group] were followed till eruption of their permanent successors. Ninety-seven dark discolored asymptomatic primary incisors were left untreated and invited for periodic clinical and radiographic examination. Of these, 28 [follow-up (FU) group] were followed till eruption of their permanent successors. The parameters examined included early extraction of the traumatized primary incisor, early or delayed eruption of the permanent successors, ectopic eruption of the permanent successor and signs of enamel hypopcalcification or hypoplasia in the permanent successor. Chi-square test was used for statistical analysis. Seven of 25 (28%) of the RCT group and 32% (nine of 28) of the FU group required early extraction. Five of 25 (20%) of the RCT group and 21% (six of 28) of the FU group showed early or delayed eruption of the permanent successors. Sixteen of 25 (64%) of the RCT group and 79% (22 of 28) of the FU group showed ectopic eruption of the permanent successors. Enamel hypopcalcification or hypoplasia in the permanent successors was equally found (36%) in both groups (nine of 25 in the RCT group and 10 of 28 in the FU group). None of differences was statistically significant. Root canal treatment of primary incisors that had change their color into a dark-gray hue following trauma with no other clinical or radiographic symptom is not necessary as it does not result in better outcomes in the primary teeth and their permanent successors. [source]


    Avulsion of primary teeth and sequelae on the permanent successors

    DENTAL TRAUMATOLOGY, Issue 6 2005
    Pia Christophersen
    Abstract,,, The purpose of the present study was to determine the frequency of avulsion of primary teeth and the location of the avulsed tooth in a representative population of Danish children. Also, the frequency and the type of developmental disturbances in the permanent successors were assessed and related to age at the time of injury. The material included dental records of 4238 children from three clinics in Municipal Dental Health Services near Copenhagen, Denmark. The children were born between 1 January 1983 and 31 December 2000. Thirty-five children (0.8%) were identified as having avulsed in all 44 primary teeth most frequently the maxillary incisors (89%). Thirty-three fully erupted permanent successors were included in the study, the prevalence of developmental disturbances was 30% (10 teeth). The results showed the risk of developmental disturbances in the permanent successors to be more frequent the younger the age at the time of injury (P = 0.04). Discolouration affected all 10 permanent teeth, but also hypoplasia and horizontal enamel hypoplasia were found. [source]


    Anomalous development of brain structure and function in spina bifida myelomeningocele

    DEVELOPMENTAL DISABILITIES RESEARCH REVIEW, Issue 1 2010
    Jenifer Juranek
    Abstract Spina bifida myelomeningocele (SBM) is a specific type of neural tube defect whereby the open neural tube at the level of the spinal cord alters brain development during early stages of gestation. Some structural anomalies are virtually unique to individuals with SBM, including a complex pattern of cerebellar dysplasia known as the Chiari II malformation. Other structural anomalies are not necessarily unique to SBM, including altered development of the corpus callosum and posterior fossa. Within SBM, tremendous heterogeneity is reflected in the degree to which brain structures are atypical in qualitative appearance and quantitative measures of morphometry. Hallmark structural features of SBM include overall reductions in posterior fossa and cerebellum size and volume. Studies of the corpus callosum have shown complex patterns of agenesis or hypoplasia along its rostral-caudal axis, with rostrum and splenium regions particularly susceptible to agenesis. Studies of cortical regions have demonstrated complex patterns of thickening, thinning, and gyrification. Diffusion tensor imaging studies have reported compromised integrity of some specific white matter pathways. Given equally complex ocular motor, motor, and cognitive phenotypes consisting of relative strengths and weaknesses that seem to align with altered structural development, studies of SBM provide new insights to our current understanding of brain structure,function associations. © 2010 Wiley-Liss, Inc. Dev Disabil Res Rev 2010;16:23,30. [source]


    C-myc as a modulator of renal stem/progenitor cell population

    DEVELOPMENTAL DYNAMICS, Issue 2 2009
    Martin Couillard
    Abstract The role of c - myc has been well-studied in gene regulation and oncogenesis but remains elusive in murine development from midgestation. We determined c - myc function during kidney development, organogenesis, and homeostasis by conditional loss of c - myc induced at two distinct phases of nephrogenesis, embryonic day (e) 11.5 and e17.5. Deletion of c - myc in early metanephric mesenchyme (e11.5) led to renal hypoplasia from e15.5 to e17.5 that was sustained until adulthood (range, 20,25%) and, hence, reproduced the human pathologic condition of renal hypoplasia. This phenotype resulted from depletion of c - myc,positive cells in cap mesenchyme, causing a ,35% marked decrease of Six2- and Cited1-stem/progenitor population and of proliferation that likely impaired self-renewal. By contrast, c - myc loss from e17.5 onward had no impact on late renal differentiation/maturation and/or homeostasis, providing evidence that c - myc is dispensable during these phases. This study identified c - myc as a modulator of renal organogenesis through regulation of stem/progenitor cell population. Developmental Dynamics 238:405,414, 2009. © 2009 Wiley-Liss, Inc. [source]


    pMesogenin1 and 2 function directly downstream of Xtbx6 in Xenopus somitogenesis and myogenesis

    DEVELOPMENTAL DYNAMICS, Issue 12 2008
    Shunsuke Tazumi
    Abstract T-box transcription factor tbx6 and basic-helix-loop-helix transcription factor pMesogenin1 are reported to be involved in paraxial mesodermal differentiation. To clarify the relationship between these genes in Xenopus laevis, we isolated pMesogenin2, which showed high homology with pMesogenin1. Both pMesogenin1 and 2 appeared to be transcriptional activators and were induced by a hormone-inducible version of Xtbx6 without secondary protein synthesis in animal cap assays. The pMesogenin2 promoter contained three potential T-box binding sites with which Xtbx6 protein was shown to interact, and a reporter gene construct containing these sites was activated by Xtbx6. Xtbx6 knockdown reduced pMesogenin1 and 2 expressions, but not vice versa. Xtbx6 and pMesogenin1 and 2 knockdowns caused similar phenotypic abnormalities including somite malformation and ventral body wall muscle hypoplasia, suggesting that Xtbx6 is a direct regulator of pMesogenin1 and 2, which are both involved in somitogenesis and myogenesis including that of body wall muscle in Xenopus laevis. Developmental Dynamics 237:3749,3761, 2008. © 2008 Wiley-Liss, Inc. [source]


    WNT signaling affects gene expression in the ventral diencephalon and pituitary gland growth

    DEVELOPMENTAL DYNAMICS, Issue 4 2008
    Mary Anne Potok
    Abstract We examined the role of WNT signaling in pituitary development by characterizing the pituitary phenotype of three WNT knockout mice and assessing the expression of WNT pathway components. Wnt5a mutants have expanded domains of Fgf10 and bone morphogenetic protein expression in the ventral diencephalon and a reduced domain of LHX3 expression in Rathke's pouch. Wnt4 mutants have mildly reduced cell differentiation, reduced POU1F1 expression, and mild anterior lobe hypoplasia. Wnt4, Wnt5a double mutants exhibit an additive pituitary phenotype of dysmorphology and mild hypoplasia. Wnt6 mutants have no obvious pituitary phenotype. We surveyed WNT expression and identified transcripts for numerous Wnts, Frizzleds, and downstream pathway members in the pituitary and ventral diencephalon. These findings support the emerging model that WNT signaling affects the pituitary gland via effects on ventral diencephalon signaling, and suggest additional Wnt genes that are worthy of functional studies. Developmental Dynamics 237:1006,1020, 2008. © 2008 Wiley-Liss, Inc. [source]


    Analysis of pancreatic endocrine development in GDF11-deficient mice

    DEVELOPMENTAL DYNAMICS, Issue 11 2006
    Darwin S. Dichmann
    Abstract Here, we examine the role of GDF11 in pancreatic development. Using in situ hybridization and reverse transcriptase-polymerase chain reaction analyses, we show that Gdf11 transcripts are expressed in embryonic pancreas epithelium before the secondary transition but decrease rapidly afterward. To determine the function of GDF11 during pancreas development, we analyzed Gdf11,/, mouse embryos. In such embryos, pancreas size is twofold reduced at embryonic day (E) 18 compared with wild-type littermates. Quantification of the different tissue compartments shows a specific hypoplasia of the exocrine compartment, while the endocrine and ductal compartments are unaffected. Notably, NGN3+ endocrine precursor cells are increased fourfold at E18, although the amount of endocrine cells in the pancreas of these animals is unchanged compared with wild-type littermates. Similarly, the maturation of endocrine cells as well as the ratio between ,- and ,-cells appears normal. Developmental Dynamics 235:3016,3025, 2006. © 2006 Wiley-Liss, Inc. [source]


    Bapx1 homeobox gene gain-of-function mice show preaxial polydactyly and activated Shh signaling in the developing limb

    DEVELOPMENTAL DYNAMICS, Issue 9 2006
    Carla Tribioli
    Abstract To explore Bapx1 homeobox gene function in embryonic control of development, we employed a gain-of-function approach to complement our previous loss-of-function mutant analysis. We show that transgenic mice overexpressing Bapx1 are affected by skeletal defects including hindlimb preaxial polydactyly and tibial hypoplasia. Bapx1 overexpression generates limb anteroposterior patterning defects including induction of Shh signaling and ectopic activation of functions downstream of Shh signaling into the anterior region of the autopod. Moreover, Bapx1 overexpression stimulates formation of limb prechondrogenic condensations. We also show that Shh is reciprocally able to activate Bapx1 expression in mouse embryos as the orthologous hedgehog (hh) does with the bagpipe/Bapx1 gene in Drosophila. Our results indicate that Bapx1 can modulate appendicular skeletal formation, that the genetic hierarchy between Shh/hh and Bapx1/bagpipe has been conserved during evolution, and that in mouse embryos these two genes can influence one another in a genetically reciprocal manner. We conclude that it is reasonable to expect overexpression of Bapx1 in certain forms of polydactyly. Developmental Dynamics 235:2483,2492, 2006. © 2006 Wiley-Liss, Inc. [source]


    Contractile activity of skeletal musculature involved in breathing is essential for normal lung cell differentiation, as revealed in Myf5,/,:MyoD,/, embryos

    DEVELOPMENTAL DYNAMICS, Issue 3 2005
    Mohammad Reza Inanlou
    Abstract In the current study, the role of contractile activity of respiratory muscles in fetal lung growth and cell differentiation was examined using Myf5,/,:MyoD,/, mouse embryos. As previously found, Myf5,/,:MyoD,/, mouse embryos had no respiratory musculature. Consequently, they suffered from pulmonary hypoplasia and died shortly after birth. The hypoplastic lung had decreased proliferation and increased apoptotic index as early as embryonic day 14.5. By contrast, only at the last gestational day, the number of lung cells expressing platelet derived growth factor B and insulin growth factor I was decreased, while the gradient of the thyroid transcription factor 1 was not maintained. Type II pneumocytes had a failure in glycogen utilization and surfactant storage and secretion but were able to synthesize the surfactant-associated proteins. Type I pneumocytes were readily detectable using an early differentiation marker (i.e., Gp38). However, the late differentiation of type I pneumocytes never occurred, as revealed by transmission electron microscopy. Together, our findings suggest that pulmonary distension due to fetal breathing-like movements plays an important role not only in lung growth but also in lung cell differentiation. Developmental Dynamics 233:772,782, 2005. © 2005 Wiley-Liss, Inc. [source]


    Outcome of severe unilateral cerebellar hypoplasia

    DEVELOPMENTAL MEDICINE & CHILD NEUROLOGY, Issue 8 2010
    ANDREA PORETTI
    Aim, Complete or subtotal absence of one cerebellar hemisphere is exceptional; only single cases have been described. We aimed to assess the long-term outcome in children with severe unilateral cerebellar hypoplasia (UCH). Method, As part of a retrospective study we describe neuroimaging features, clinical findings, and cognitive outcomes of seven children with UCH (five males, two females; age at first magnetic resonance imaging [MRI]: median 1y 3mo, range 9d,8y 10mo; age at latest follow-up: median 6y 6mo, range 2y 3mo,14y 11mo). Results, One child had abnormalities on prenatal MRI at 21 weeks' gestation. The left cerebellar hemisphere was affected in five children, and the right hemisphere in two children. The vermis was involved in five children. The volume of the posterior fossa was variable. At the latest follow-up, neurological findings included truncal ataxia and muscular hypotonia in five children, limb ataxia in three patients, and head nodding in two patients. Three children had learning disability*, five had speech and language disorders, and one had a severe behavioural disorder. Interpretation, Severe UCH is a residual change after a disruptive prenatal cerebellar insult, most likely haemorrhagic. The outcome is variable, ranging from almost normal development to marked developmental impairment. Ataxia is a frequent but not a leading sign. It seems that involvement of the cerebellar vermis is often, but not consistently, associated with a poorer cognitive outcome, whereas an intact vermis is associated with normal outcome and no truncal ataxia. [source]


    Corpus callosum and posterior fossa development in monozygotic females: a morphometric MRI study of Turner syndrome

    DEVELOPMENTAL MEDICINE & CHILD NEUROLOGY, Issue 5 2003
    Susannah L Fryer BA
    Previous neuroimaging research in Turner syndrome (TS) has indicated parietal lobe anomalies, while anomalies in other brain loci have been less well-substantiated. This study focused on potential cerebellar abnormalities and possible disruptions of interhemispheric (parietal) callosal connections in individuals with TS. Twenty-seven female children and adolescents with TS (mean age 13 years, SD 4 years 2 months) and 27 age-matched female control individuals (mean age 13 years 2 months, SD 4 years 1 month) underwent MRI. Age range of all participants was 7 to 20 years. Morphometric analyses of midline brain structures were conducted using standardized, reliable methods. When compared with control participants, females with TS showed reduced areas of the genu of the corpus callosum, the pons, and vermis lobules VI,VII, and an increased area of the fourth ventricle. No group difference in intracranial area measurements was observed. The reduced area of the genu in TS may reflect compromised connectivity between inferior parietal regions. Further, cerebellar vermis hypoplasia associated with TS agrees with literature that suggests the posterior fossa as a region prone to structural alterations in the face of early developmental insult. [source]


    Brain dysmorphology in individuals with severe prenatal alcohol exposure

    DEVELOPMENTAL MEDICINE & CHILD NEUROLOGY, Issue 3 2001
    Sarah L Archibald MA
    Our previous studies revealed abnormalities on structural MRI (sMRI) in small groups of children exposed to alcohol prenatally. Microcephaly, disproportionately reduced basal ganglia volume, and abnormalities of the cerebellar vermis and corpus callosum were demonstrated. The present study used sMRI to examine in detail the regional pattern of brain hypoplasia resulting from prenatal exposure to alcohol using a higher resolution imaging protocol and larger sample sizes than reported previously. Fourteen participants (mean 11.4 years; eight females, six males) with fetal alcohol syndrome (FAS) and 12 participants (mean 14.8 years; four females, eight males) with prenatal exposure to alcohol (PEA) but without the facial features of FAS were compared to a group of 41 control participants (mean 12.8 years, 20 females, 21 males). Findings of significant microcephaly and disproportionately reduced basal ganglia volumes in the FAS group were confirmed. Novel findings were that in FAS participants, white matter volumes were more affected than gray matter volumes in the cerebrum, and parietal lobes were more affected than temporal and occipital lobes. Among subcortical structures, in contrast to the disproportionate effects on caudate nucleus, the hippocampus was relatively preserved in FAS participants. Differences between the PEA group and controls were generally non-significant; however, among a few of the structures most affected in FAS participants, there was some evidence for volume reduction in PEA participants as well, specifically in basal ganglia and the parietal lobe. There were no group differences in cerebral volume asymmetries. Severe prenatal alcohol exposure appears to produce a specific pattern of brain hypoplasia. [source]


    Entities and frequency of neonatal diabetes: data from the diabetes documentation and quality management system (DPV)

    DIABETIC MEDICINE, Issue 6 2010
    J. Grulich-Henn
    Diabet. Med. 27, 709,712 (2010) Abstract Aims, The aim of this study was to elucidate the entities and the frequency of neonatal diabetes mellitus (NDM) in a large representative database for paediatric diabetes patients in Germany and Austria. Methods, Based on the continuous diabetes data acquisition system for prospective surveillance (DPV), which includes 51 587 patients with onset of diabetes before the age of 18 years from 299 centres in Germany and Austria, we searched for patients with onset of diabetes mellitus in the first 6 months of life. Results, Ninety patients were identified, comprising 0.17% of all paediatric cases in the DPV registry. This represented an incidence of approximately one case in 89 000 live births in Germany. A monogenic basis for NDM was established in 30 subjects (seven UPD6, 10 KCNJ11, seven ABCC8, two FOXP3, two PDX1, one INS, one EIF2AK3). Pancreatic hypoplasia or agenesis was reported in 10 patients and seven subjects were classified as having Type 1 diabetes by their centres. Transient neonatal diabetes (TNDM) accounted for approximately 10% of all cases with NDM. No aetiology was defined in 41 subjects, which may reflect incomplete genetic testing or novel genetic aetiologies. Conclusion, Based on a large database, we identified a higher rate of NDM in Germany than has been reported previously. Full molecular genetic testing should be performed in all patients diagnosed before 6 months of age. [source]


    The Use of 3D Contrast-Enhanced CT Reconstructions to Project Images of Vascular Rings and Coarctation of the Aorta

    ECHOCARDIOGRAPHY, Issue 1 2009
    Thomas G. Di Sessa M.D.
    Background: Aortic arch and pulmonary artery anomalies make up a group of vascular structures that have complex three-dimensional (3D) shapes. Tortuosity as well as hypoplasia or atresia of segments of the aortic arch or pulmonary artery makes the conventional two-dimensional (2D) imaging difficult. Methods: Nine patients with native coarctation or recoarctation and 4 patients with a vascular ring had a CT scan as a part of their clinical evaluation. There were 7 males. The mean age was 11.7 years. (range 19 days to 29 years) The mean weight was 22.7 kg (range 3.3,139.0 kg). The dicom data from contrast CT scans were converted by the Amira software package into a 3D image. The areas of interest were selected. The images were then projected in 3D on a standard video monitor and could be rotated 360° in any dimension. Results: Adequate CT scans and 3D reconstructions were obtained in 12 of 13 patients. There were 85,1,044 slices obtained in the adequate studies. We could not reconstruct a 3D image from a patient's CT scan that had only 22 slices. The anatomy defined by 3D was compared to 2D CT imaging and confirmed by cardiac catheterization or direct visualization in the operating room in the 12 patients with adequate 3D reconstructions. In 5 of 12 patients, 3D reconstructions provided valuable spatial information not observed in the conventional 2D scans. Conclusion: We believe that 3D reconstruction of contrast-enhanced CT scans of these complex structures provides additional valuable information that is helpful in the decision-making process. [source]